Flour process and apparatus



E. F. CLARK.

FLOUR PROCESS AND APPARATUS.

APPLICATION FILED NOV. 21, 1918- Patented Nov. 30, 1920.

UNITED STATES PATENT OFFICE.

EDWARD F. CLARK, 0F MINNEAPOLIS, MINNESOTA, ASSIGNOR TO CLARK MILLING COMPANY, OF MINNEAPOLIS, MINNESOTA, A CORPORATION OF MINNESOTA.

FLOUR rnoonss AND APPARATUS.

Specification of Letters Patent.

Patented Nov. 30, 1920.

Application filed November 21, 1918. Serial No. 263,533.

To all whom it may concern:

Be it known that I, EDWARD F. CLARK, citizen of the United States, resident of Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Flour Processes and Apparatus, of Which the following is a specification. I

My invention relates to improvements in the process of making flour from wheat or other grains and also in the mechanism by which such. processes may be carried out.

On October 20th, 1903, Letters Patent of the United States No. 741,887 were issued to me for a certain new and useful improvement in flour processes. This invention has been continuously in use, and has proved of great value, from the fact of its superior granulating action, which reduces the whole body of the berry to middlings and at the same time makes less break flour to the reduction, than any method known to me.

I have found, however, that the volume of middlings made by my process is so large that the channels for discharge provided were inadequate, resulting in many of the largest and best middlings being broken again, one or more times, before escaping from the rolls. Therefore I have devised my present invention to remedy this difiiculty, as an improvement upon the apparatus disclosedv in my former patent, and upon the process therein described and claimed. p

In the accompanying drawings forming part of this specification,

Figure 1 is a plan view of a pair of rolls embodying my invention.

' Fig. 2 is an elevation of the rolls with the shafts shown in section. I

Fig. 3 is an enlarged detail of a portion of the surface of one of the rolls. This section may be considered as broken out of any portion of either of the rolls shown in Fig. 1 of the drawings.

Fig. 4: is a perspective view on a larger scaleshowing in detail a few of the interrupted ribs.

In carrying out my present invention I employ one or more pairs of spirally grooved grinding rolls 2, 3. These rolls have very sharp spiral corrugations i, for example, as 10 or 12 inches to the foot, substantially as with the rolls illustrated in my former I patent.

cause the corrugations on the contacting surfaces of the rolls to run'at a considerable angle to each other, one of said rolls being driven 'at a slow speed and the other at a high speed whereby the berries of grain may be subjected to a raking action by the corrugations of one rollupon the other roll.

In order, however, to permit the middlings to escape more readily from the rolls and in a coarser condition, I provide each of the rolls with another set of spiral corrugations 5 extending around the roll substantially at a considerable angle to the first named spirals. This last named set of spirals or grooves, which I prefer to designate the second set of spirals or grooves, the depth and width of which is made to conform to the class of stock to be ground, are spaced farther apart than the original spirals. As a result of this the coarse middlings produced by the raking actionof one set of corrugations upon the other, readily escape through F an angle on both of the rolls 2 and 3, each roll is provided either with a series of points ,or short ribs, depending upon the width of spacing of the corrugations 5, the corrugations of each roll forming between them interrupted ribs having downwardly and outvardly sloping ends. As in operation one of the rolls is driven at a greater speed'than the other the grain is disintegrated by means of series of points, one series moving at a higher rate of'speed and passing the other series moving at a lower rate of speed. This mode of operation produces ashelling or picking action of the middlings out of the berries with little or no crushing effect. It will be understood that with the radual re-. duction system of milling it is (Tesirable to get all of the flour producing part of the berry into the form of granular middlings, and to produce, while getting such middlings, just as small an ai'nount :of flour (called break flour) as possible. The mode of operation obtained with these rolls reduces the whole interior of the berry to a maximum quantity of large, uniform mid dlings. These middlings are permitted to readily escape from the rolls through both series of grooves which form outlets'therefor. lVith this arrangement the amount of break flour produced by the action of these rolls is reduced to a minimum. When the second series of corrugations 5 is spaced more widely apart than the other corrugations at on the same roll, the surface of the rolls has the appearance of a series of short ribs, as represented in Fig. 3 of the drawing with outlets at each cross-cut, and when spaced more closely together the surface of the roll has the appearance of teeth with outlets between each pair of such teeth. lVhether the surface of the roll is divided into a series of short ribs or a series of teeth, the disintegrating motion is much the same, because these short ribs or teeth on one roll cross the similar ribs 01' teeth on the other roll at an angle the opposing surfaces on the rolls are substantially points, and I thus get this disintegrating action on the berry hereinbet'ore described, reducing the entire interior thereof to large granular middlings with practically no production of break flour.

I claim as my invention:

1. In an apparatus for producing flour from wheat or other grains, a pair of grinding rolls having spiral corrugations extending in the same direction and at a pitch of spiral that causes the corrugations upon the contacting surfaces of the rolls to cross one another at an angle, and with a second set of spiral corrugations upon each roll, sub stantially at an angle to the first named set of corrugations, the corrugations of each roll forming between them interrupted ribs having all sides downwardly and outwardly sloping, in combination with means for driving said rolls, substantially as described.

2. In an apparatus for producing flour from wheat or other grains, a pair of grinding rolls having spiral. corrugations in the same direction, and at a pitch of spiral that causes the corrugations upon the contacting surfaces of the rolls to cross one another at an angle, and with a second set of spiral corrugations upon each roll running substantially at an angle to the first named set of corrugations, said second set of corruga tions being spaced more widely apart than the first set, in combination with means for driving said rolls, substantially as described. 3. In an apparatus for producing flour from wheat or other grains, a pair of grinding rolls having spiral corrugations running in the same direction, and a pitch of spiral that causes the corrugations upon the contacting surfaces of the rolls to cross one another at substantially right angles, and with a second set of spiral corrugations upon each roll running substantially at right angles to the first named set of spiral corrugations, saidsecond set of corrugations being spaced more widely apart than the first set, in combination with means for driving said rolls, substantially as described.

at. The process of reducing wheat or other grain, which consists in passing berries between rolls, having one set of spiral corrugations running in the same direction, and of a pitch of spiral that causes the corrugations upon the contacting surfaces oi the rolls to cross one another at an angle, and a second set of corrugations upon each roll running substantially at an angle to the first named set of corrugations, said second set of corrugations being spaced much wider apart than the first set, whereby the berries are subjected to the raking action of one series of grinding points traveling past another series of similar points, and the mid dlings produced are permitted to escape in a coarse or unbrokencondition.

The process of reducing wheat or other I which consists in passing berries between rolls having spiral corrugations running in the same direction, and of a degree oi piral that causes the corrugations upon the contacting surfaces of the rolls to cross one another, substantially at right angles, and a second series of spiral corrugations upon each roll passing the first named spiral corrugations at an angle, one of said rolls being driven at a slow speed and the other at a highspeed whereby the berries are subjected to the raking action of one series of grinding points traveling past another series of similar points, and the middlings are permitted to escape from the rolls in a coarse or unbroken condition.

In witness whereoi I have hereunto set my hand this 15th day of November 1918.

EDWVARD F. CLARK. 

